The Responses Of Root Border Cells Of Pea (Pisum Sativum) And Its Cell Wall To Aluminum Toxicity At Different B Levels

Root border cells are recently defined alive population sloughed from root tips and loosely adhered in the water soluble mucilage, and the root tip is just the target of Al toxicity, thus it was guessed that border cells might function crucially in the response to Al toxicity. Structure stability of cell wall seems particularly important about keeping cell vigor and function. Boron is regarded as the important component part of cell wall, and Al is regarded as a cation with strong binding capacity to exchange targets in cell wall. It has been suggested that B could alleviate Al toxicity and proved by some researches, but still evidences lacks and the mechanism is not clear. The variation of cell wall characteristics of root border cells of pea induced by Al toxicity at different B levels provided some evidences to the hypothesis..Mist culture was adopted in the developing of root border cells to study effect of solution B on alleviating Al toxicity including change of cell wall composition of root border cellls and root at different B and Al levels via adding B and Al in the soaking water and mist during the culture process. The results are : B prevents the drop of border cell viability and the cell number caused by Al treatment, increase B combining cell wall and decreases the absorb of Al by border cells, thus alleaviates the Al toxicity of border cells and root. Cell wall characteristics are also promising to be important factors in B and Al relationship.1. Our research provided evidence that B pretreatment with seed soaking and / or B in mist solution enhanced B levels in seedling. B could increase the viability while decrease cell number of border cells, and it also could prevent the drop of border cell viability at Al stress, which indicated that B could alleviate Al toxicity through promoting cell viability and keep a steady cell quantity.2. Cell viability and cell number was reduced by the increase of Al concentration, but cell viability at 500μmol/L is higher than 50μmol/L significantly which showed that Al induced cell death at dosage dependent manner at lower Al concentration but not at higher concentration which might relate to the response of border cells to Al toxicity—the...